The referee supervised the boot switch between the conveniently similarly-sized pair in the nineteenth minute, fielding queries from confused protesting players in the process.
As one commenter explains though, there was a relatively mundane explanation behind the exchange:
They mention in the video there is an injury to the crew. What actually happened was the 4th had to switch with the AR as he was injured. They switched shoes so the AR was able to run on the pitch. Still a rare occurrence, but not just switching shoes for no reason ;) !
See the full stoppage as the assistant referees swap shoes during Real Salt Lake vs Chicago Fire in the video above.
Plus the league tweeted a gif:
If the shoe fits… pic.twitter.com/CE3NaERT06
— Major League Soccer (@MLS) August 7, 2016
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